1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Base unit test (KUnit) API.
  4 *
  5 * Copyright (C) 2019, Google LLC.
  6 * Author: Brendan Higgins <brendanhiggins@google.com>
  7 */
  8
  9#include <kunit/test.h>
 10#include <kunit/test-bug.h>
 11#include <linux/kernel.h>
 12#include <linux/kref.h>
 13#include <linux/sched/debug.h>
 14#include <linux/sched.h>
 15
 16#include "debugfs.h"
 17#include "string-stream.h"
 18#include "try-catch-impl.h"
 19
 20#if IS_BUILTIN(CONFIG_KUNIT)
 21/*
 22 * Fail the current test and print an error message to the log.
 23 */
 24void __kunit_fail_current_test(const char *file, int line, const char *fmt, ...)
 25{
 26	va_list args;
 27	int len;
 28	char *buffer;
 29
 30	if (!current->kunit_test)
 31		return;
 32
 33	kunit_set_failure(current->kunit_test);
 34
 35	/* kunit_err() only accepts literals, so evaluate the args first. */
 36	va_start(args, fmt);
 37	len = vsnprintf(NULL, 0, fmt, args) + 1;
 38	va_end(args);
 39
 40	buffer = kunit_kmalloc(current->kunit_test, len, GFP_KERNEL);
 41	if (!buffer)
 42		return;
 43
 44	va_start(args, fmt);
 45	vsnprintf(buffer, len, fmt, args);
 46	va_end(args);
 47
 48	kunit_err(current->kunit_test, "%s:%d: %s", file, line, buffer);
 49	kunit_kfree(current->kunit_test, buffer);
 50}
 51EXPORT_SYMBOL_GPL(__kunit_fail_current_test);
 52#endif
 53
 54/*
 55 * Append formatted message to log, size of which is limited to
 56 * KUNIT_LOG_SIZE bytes (including null terminating byte).
 57 */
 58void kunit_log_append(char *log, const char *fmt, ...)
 59{
 60	char line[KUNIT_LOG_SIZE];
 61	va_list args;
 62	int len_left;
 63
 64	if (!log)
 65		return;
 66
 67	len_left = KUNIT_LOG_SIZE - strlen(log) - 1;
 68	if (len_left <= 0)
 69		return;
 70
 71	va_start(args, fmt);
 72	vsnprintf(line, sizeof(line), fmt, args);
 73	va_end(args);
 74
 75	strncat(log, line, len_left);
 76}
 77EXPORT_SYMBOL_GPL(kunit_log_append);
 78
 79size_t kunit_suite_num_test_cases(struct kunit_suite *suite)
 80{
 81	struct kunit_case *test_case;
 82	size_t len = 0;
 83
 84	kunit_suite_for_each_test_case(suite, test_case)
 85		len++;
 86
 87	return len;
 88}
 89EXPORT_SYMBOL_GPL(kunit_suite_num_test_cases);
 90
 91static void kunit_print_subtest_start(struct kunit_suite *suite)
 92{
 93	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "# Subtest: %s",
 94		  suite->name);
 95	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "1..%zd",
 96		  kunit_suite_num_test_cases(suite));
 97}
 98
 99static void kunit_print_ok_not_ok(void *test_or_suite,
100				  bool is_test,
101				  enum kunit_status status,
102				  size_t test_number,
103				  const char *description,
104				  const char *directive)
105{
106	struct kunit_suite *suite = is_test ? NULL : test_or_suite;
107	struct kunit *test = is_test ? test_or_suite : NULL;
108	const char *directive_header = (status == KUNIT_SKIPPED) ? " # SKIP " : "";
109
110	/*
111	 * We do not log the test suite results as doing so would
112	 * mean debugfs display would consist of the test suite
113	 * description and status prior to individual test results.
114	 * Hence directly printk the suite status, and we will
115	 * separately seq_printf() the suite status for the debugfs
116	 * representation.
117	 */
118	if (suite)
119		pr_info("%s %zd - %s%s%s\n",
120			kunit_status_to_ok_not_ok(status),
121			test_number, description, directive_header,
122			(status == KUNIT_SKIPPED) ? directive : "");
123	else
124		kunit_log(KERN_INFO, test,
125			  KUNIT_SUBTEST_INDENT "%s %zd - %s%s%s",
126			  kunit_status_to_ok_not_ok(status),
127			  test_number, description, directive_header,
128			  (status == KUNIT_SKIPPED) ? directive : "");
129}
130
131enum kunit_status kunit_suite_has_succeeded(struct kunit_suite *suite)
132{
133	const struct kunit_case *test_case;
134	enum kunit_status status = KUNIT_SKIPPED;
135
136	kunit_suite_for_each_test_case(suite, test_case) {
137		if (test_case->status == KUNIT_FAILURE)
138			return KUNIT_FAILURE;
139		else if (test_case->status == KUNIT_SUCCESS)
140			status = KUNIT_SUCCESS;
141	}
142
143	return status;
144}
145EXPORT_SYMBOL_GPL(kunit_suite_has_succeeded);
146
147static void kunit_print_subtest_end(struct kunit_suite *suite)
148{
149	static size_t kunit_suite_counter = 1;
150
151	kunit_print_ok_not_ok((void *)suite, false,
152			      kunit_suite_has_succeeded(suite),
153			      kunit_suite_counter++,
154			      suite->name,
155			      suite->status_comment);
156}
157
158unsigned int kunit_test_case_num(struct kunit_suite *suite,
159				 struct kunit_case *test_case)
160{
161	struct kunit_case *tc;
162	unsigned int i = 1;
163
164	kunit_suite_for_each_test_case(suite, tc) {
165		if (tc == test_case)
166			return i;
167		i++;
168	}
169
170	return 0;
171}
172EXPORT_SYMBOL_GPL(kunit_test_case_num);
173
174static void kunit_print_string_stream(struct kunit *test,
175				      struct string_stream *stream)
176{
177	struct string_stream_fragment *fragment;
178	char *buf;
179
180	if (string_stream_is_empty(stream))
181		return;
182
183	buf = string_stream_get_string(stream);
184	if (!buf) {
185		kunit_err(test,
186			  "Could not allocate buffer, dumping stream:\n");
187		list_for_each_entry(fragment, &stream->fragments, node) {
188			kunit_err(test, "%s", fragment->fragment);
189		}
190		kunit_err(test, "\n");
191	} else {
192		kunit_err(test, "%s", buf);
193		kunit_kfree(test, buf);
194	}
195}
196
197static void kunit_fail(struct kunit *test, struct kunit_assert *assert)
198{
199	struct string_stream *stream;
200
201	kunit_set_failure(test);
202
203	stream = alloc_string_stream(test, GFP_KERNEL);
204	if (!stream) {
205		WARN(true,
206		     "Could not allocate stream to print failed assertion in %s:%d\n",
207		     assert->file,
208		     assert->line);
209		return;
210	}
211
212	assert->format(assert, stream);
213
214	kunit_print_string_stream(test, stream);
215
216	WARN_ON(string_stream_destroy(stream));
217}
218
219static void __noreturn kunit_abort(struct kunit *test)
220{
221	kunit_try_catch_throw(&test->try_catch); /* Does not return. */
222
223	/*
224	 * Throw could not abort from test.
225	 *
226	 * XXX: we should never reach this line! As kunit_try_catch_throw is
227	 * marked __noreturn.
228	 */
229	WARN_ONCE(true, "Throw could not abort from test!\n");
230}
231
232void kunit_do_assertion(struct kunit *test,
233			struct kunit_assert *assert,
234			bool pass,
235			const char *fmt, ...)
236{
237	va_list args;
238
239	if (pass)
240		return;
241
242	va_start(args, fmt);
243
244	assert->message.fmt = fmt;
245	assert->message.va = &args;
246
247	kunit_fail(test, assert);
248
249	va_end(args);
250
251	if (assert->type == KUNIT_ASSERTION)
252		kunit_abort(test);
253}
254EXPORT_SYMBOL_GPL(kunit_do_assertion);
255
256void kunit_init_test(struct kunit *test, const char *name, char *log)
257{
258	spin_lock_init(&test->lock);
259	INIT_LIST_HEAD(&test->resources);
260	test->name = name;
261	test->log = log;
262	if (test->log)
263		test->log[0] = '\0';
264	test->status = KUNIT_SUCCESS;
265	test->status_comment[0] = '\0';
266}
267EXPORT_SYMBOL_GPL(kunit_init_test);
268
269/*
270 * Initializes and runs test case. Does not clean up or do post validations.
271 */
272static void kunit_run_case_internal(struct kunit *test,
273				    struct kunit_suite *suite,
274				    struct kunit_case *test_case)
275{
276	if (suite->init) {
277		int ret;
278
279		ret = suite->init(test);
280		if (ret) {
281			kunit_err(test, "failed to initialize: %d\n", ret);
282			kunit_set_failure(test);
283			return;
284		}
285	}
286
287	test_case->run_case(test);
288}
289
290static void kunit_case_internal_cleanup(struct kunit *test)
291{
292	kunit_cleanup(test);
293}
294
295/*
296 * Performs post validations and cleanup after a test case was run.
297 * XXX: Should ONLY BE CALLED AFTER kunit_run_case_internal!
298 */
299static void kunit_run_case_cleanup(struct kunit *test,
300				   struct kunit_suite *suite)
301{
302	if (suite->exit)
303		suite->exit(test);
304
305	kunit_case_internal_cleanup(test);
306}
307
308struct kunit_try_catch_context {
309	struct kunit *test;
310	struct kunit_suite *suite;
311	struct kunit_case *test_case;
312};
313
314static void kunit_try_run_case(void *data)
315{
316	struct kunit_try_catch_context *ctx = data;
317	struct kunit *test = ctx->test;
318	struct kunit_suite *suite = ctx->suite;
319	struct kunit_case *test_case = ctx->test_case;
320
321	current->kunit_test = test;
322
323	/*
324	 * kunit_run_case_internal may encounter a fatal error; if it does,
325	 * abort will be called, this thread will exit, and finally the parent
326	 * thread will resume control and handle any necessary clean up.
327	 */
328	kunit_run_case_internal(test, suite, test_case);
329	/* This line may never be reached. */
330	kunit_run_case_cleanup(test, suite);
331}
332
333static void kunit_catch_run_case(void *data)
334{
335	struct kunit_try_catch_context *ctx = data;
336	struct kunit *test = ctx->test;
337	struct kunit_suite *suite = ctx->suite;
338	int try_exit_code = kunit_try_catch_get_result(&test->try_catch);
339
340	if (try_exit_code) {
341		kunit_set_failure(test);
342		/*
343		 * Test case could not finish, we have no idea what state it is
344		 * in, so don't do clean up.
345		 */
346		if (try_exit_code == -ETIMEDOUT) {
347			kunit_err(test, "test case timed out\n");
348		/*
349		 * Unknown internal error occurred preventing test case from
350		 * running, so there is nothing to clean up.
351		 */
352		} else {
353			kunit_err(test, "internal error occurred preventing test case from running: %d\n",
354				  try_exit_code);
355		}
356		return;
357	}
358
359	/*
360	 * Test case was run, but aborted. It is the test case's business as to
361	 * whether it failed or not, we just need to clean up.
362	 */
363	kunit_run_case_cleanup(test, suite);
364}
365
366/*
367 * Performs all logic to run a test case. It also catches most errors that
368 * occur in a test case and reports them as failures.
369 */
370static void kunit_run_case_catch_errors(struct kunit_suite *suite,
371					struct kunit_case *test_case,
372					struct kunit *test)
373{
374	struct kunit_try_catch_context context;
375	struct kunit_try_catch *try_catch;
376
377	kunit_init_test(test, test_case->name, test_case->log);
378	try_catch = &test->try_catch;
379
380	kunit_try_catch_init(try_catch,
381			     test,
382			     kunit_try_run_case,
383			     kunit_catch_run_case);
384	context.test = test;
385	context.suite = suite;
386	context.test_case = test_case;
387	kunit_try_catch_run(try_catch, &context);
388
389	/* Propagate the parameter result to the test case. */
390	if (test->status == KUNIT_FAILURE)
391		test_case->status = KUNIT_FAILURE;
392	else if (test_case->status != KUNIT_FAILURE && test->status == KUNIT_SUCCESS)
393		test_case->status = KUNIT_SUCCESS;
394}
395
396int kunit_run_tests(struct kunit_suite *suite)
397{
398	char param_desc[KUNIT_PARAM_DESC_SIZE];
399	struct kunit_case *test_case;
400
401	kunit_print_subtest_start(suite);
402
403	kunit_suite_for_each_test_case(suite, test_case) {
404		struct kunit test = { .param_value = NULL, .param_index = 0 };
405		test_case->status = KUNIT_SKIPPED;
406
407		if (test_case->generate_params) {
408			/* Get initial param. */
409			param_desc[0] = '\0';
410			test.param_value = test_case->generate_params(NULL, param_desc);
411		}
412
413		do {
414			kunit_run_case_catch_errors(suite, test_case, &test);
415
416			if (test_case->generate_params) {
417				if (param_desc[0] == '\0') {
418					snprintf(param_desc, sizeof(param_desc),
419						 "param-%d", test.param_index);
420				}
421
422				kunit_log(KERN_INFO, &test,
423					  KUNIT_SUBTEST_INDENT
424					  "# %s: %s %d - %s",
425					  test_case->name,
426					  kunit_status_to_ok_not_ok(test.status),
427					  test.param_index + 1, param_desc);
428
429				/* Get next param. */
430				param_desc[0] = '\0';
431				test.param_value = test_case->generate_params(test.param_value, param_desc);
432				test.param_index++;
433			}
434		} while (test.param_value);
435
436		kunit_print_ok_not_ok(&test, true, test_case->status,
437				      kunit_test_case_num(suite, test_case),
438				      test_case->name,
439				      test.status_comment);
440	}
441
442	kunit_print_subtest_end(suite);
443
444	return 0;
445}
446EXPORT_SYMBOL_GPL(kunit_run_tests);
447
448static void kunit_init_suite(struct kunit_suite *suite)
449{
450	kunit_debugfs_create_suite(suite);
451	suite->status_comment[0] = '\0';
452}
453
454int __kunit_test_suites_init(struct kunit_suite * const * const suites)
455{
456	unsigned int i;
457
458	for (i = 0; suites[i] != NULL; i++) {
459		kunit_init_suite(suites[i]);
460		kunit_run_tests(suites[i]);
461	}
462	return 0;
463}
464EXPORT_SYMBOL_GPL(__kunit_test_suites_init);
465
466static void kunit_exit_suite(struct kunit_suite *suite)
467{
468	kunit_debugfs_destroy_suite(suite);
469}
470
471void __kunit_test_suites_exit(struct kunit_suite **suites)
472{
473	unsigned int i;
474
475	for (i = 0; suites[i] != NULL; i++)
476		kunit_exit_suite(suites[i]);
477}
478EXPORT_SYMBOL_GPL(__kunit_test_suites_exit);
479
480/*
481 * Used for static resources and when a kunit_resource * has been created by
482 * kunit_alloc_resource().  When an init function is supplied, @data is passed
483 * into the init function; otherwise, we simply set the resource data field to
484 * the data value passed in.
485 */
486int kunit_add_resource(struct kunit *test,
487		       kunit_resource_init_t init,
488		       kunit_resource_free_t free,
489		       struct kunit_resource *res,
490		       void *data)
491{
492	int ret = 0;
493	unsigned long flags;
494
495	res->free = free;
496	kref_init(&res->refcount);
497
498	if (init) {
499		ret = init(res, data);
500		if (ret)
501			return ret;
502	} else {
503		res->data = data;
504	}
505
506	spin_lock_irqsave(&test->lock, flags);
507	list_add_tail(&res->node, &test->resources);
508	/* refcount for list is established by kref_init() */
509	spin_unlock_irqrestore(&test->lock, flags);
510
511	return ret;
512}
513EXPORT_SYMBOL_GPL(kunit_add_resource);
514
515int kunit_add_named_resource(struct kunit *test,
516			     kunit_resource_init_t init,
517			     kunit_resource_free_t free,
518			     struct kunit_resource *res,
519			     const char *name,
520			     void *data)
521{
522	struct kunit_resource *existing;
523
524	if (!name)
525		return -EINVAL;
526
527	existing = kunit_find_named_resource(test, name);
528	if (existing) {
529		kunit_put_resource(existing);
530		return -EEXIST;
531	}
532
533	res->name = name;
534
535	return kunit_add_resource(test, init, free, res, data);
536}
537EXPORT_SYMBOL_GPL(kunit_add_named_resource);
538
539struct kunit_resource *kunit_alloc_and_get_resource(struct kunit *test,
540						    kunit_resource_init_t init,
541						    kunit_resource_free_t free,
542						    gfp_t internal_gfp,
543						    void *data)
544{
545	struct kunit_resource *res;
546	int ret;
547
548	res = kzalloc(sizeof(*res), internal_gfp);
549	if (!res)
550		return NULL;
551
552	ret = kunit_add_resource(test, init, free, res, data);
553	if (!ret) {
554		/*
555		 * bump refcount for get; kunit_resource_put() should be called
556		 * when done.
557		 */
558		kunit_get_resource(res);
559		return res;
560	}
561	return NULL;
562}
563EXPORT_SYMBOL_GPL(kunit_alloc_and_get_resource);
564
565void kunit_remove_resource(struct kunit *test, struct kunit_resource *res)
566{
567	unsigned long flags;
568
569	spin_lock_irqsave(&test->lock, flags);
570	list_del(&res->node);
571	spin_unlock_irqrestore(&test->lock, flags);
572	kunit_put_resource(res);
573}
574EXPORT_SYMBOL_GPL(kunit_remove_resource);
575
576int kunit_destroy_resource(struct kunit *test, kunit_resource_match_t match,
577			   void *match_data)
578{
579	struct kunit_resource *res = kunit_find_resource(test, match,
580							 match_data);
581
582	if (!res)
583		return -ENOENT;
584
585	kunit_remove_resource(test, res);
586
587	/* We have a reference also via _find(); drop it. */
588	kunit_put_resource(res);
589
590	return 0;
591}
592EXPORT_SYMBOL_GPL(kunit_destroy_resource);
593
594struct kunit_kmalloc_array_params {
595	size_t n;
596	size_t size;
597	gfp_t gfp;
598};
599
600static int kunit_kmalloc_array_init(struct kunit_resource *res, void *context)
601{
602	struct kunit_kmalloc_array_params *params = context;
603
604	res->data = kmalloc_array(params->n, params->size, params->gfp);
605	if (!res->data)
606		return -ENOMEM;
607
608	return 0;
609}
610
611static void kunit_kmalloc_array_free(struct kunit_resource *res)
612{
613	kfree(res->data);
614}
615
616void *kunit_kmalloc_array(struct kunit *test, size_t n, size_t size, gfp_t gfp)
617{
618	struct kunit_kmalloc_array_params params = {
619		.size = size,
620		.n = n,
621		.gfp = gfp
622	};
623
624	return kunit_alloc_resource(test,
625				    kunit_kmalloc_array_init,
626				    kunit_kmalloc_array_free,
627				    gfp,
628				    &params);
629}
630EXPORT_SYMBOL_GPL(kunit_kmalloc_array);
631
632void kunit_kfree(struct kunit *test, const void *ptr)
633{
634	struct kunit_resource *res;
635
636	res = kunit_find_resource(test, kunit_resource_instance_match,
637				  (void *)ptr);
638
639	/*
640	 * Removing the resource from the list of resources drops the
641	 * reference count to 1; the final put will trigger the free.
642	 */
643	kunit_remove_resource(test, res);
644
645	kunit_put_resource(res);
646
647}
648EXPORT_SYMBOL_GPL(kunit_kfree);
649
650void kunit_cleanup(struct kunit *test)
651{
652	struct kunit_resource *res;
653	unsigned long flags;
654
655	/*
656	 * test->resources is a stack - each allocation must be freed in the
657	 * reverse order from which it was added since one resource may depend
658	 * on another for its entire lifetime.
659	 * Also, we cannot use the normal list_for_each constructs, even the
660	 * safe ones because *arbitrary* nodes may be deleted when
661	 * kunit_resource_free is called; the list_for_each_safe variants only
662	 * protect against the current node being deleted, not the next.
663	 */
664	while (true) {
665		spin_lock_irqsave(&test->lock, flags);
666		if (list_empty(&test->resources)) {
667			spin_unlock_irqrestore(&test->lock, flags);
668			break;
669		}
670		res = list_last_entry(&test->resources,
671				      struct kunit_resource,
672				      node);
673		/*
674		 * Need to unlock here as a resource may remove another
675		 * resource, and this can't happen if the test->lock
676		 * is held.
677		 */
678		spin_unlock_irqrestore(&test->lock, flags);
679		kunit_remove_resource(test, res);
680	}
681	current->kunit_test = NULL;
682}
683EXPORT_SYMBOL_GPL(kunit_cleanup);
684
685static int __init kunit_init(void)
686{
687	kunit_debugfs_init();
688
689	return 0;
690}
691late_initcall(kunit_init);
692
693static void __exit kunit_exit(void)
694{
695	kunit_debugfs_cleanup();
696}
697module_exit(kunit_exit);
698
699MODULE_LICENSE("GPL v2");